Wedge-key.



W. G. KIRCHHOFP.

WEDGE KEY. APPLICATION FILED JULY 24 1911. r 1,025,278. Patented May 7, 1912.

.\l I I ll v r A v 7 rd w a r I a I UNITED STATES" PATENT OFFICE.

WILLIAM, B. KIRCHI-IOFF, OF ST. LOUIS, MISSOURI;

WEDGELA-KEY.

Specification of Letters Patent.

Patented May 7 1912.

Application filed July 24, 1911. Serial No. 640,187.

To all whom it may concern:

Be it known that I, WILLIAM G. KIno1-I IIOFF, a citizen of the United States, residing at St. Louis, Missouri, have invented a certain new and useful Improvement in 'VVedge-Keys, of which the following is a full, clear, and exact description, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, forming part of this specification, in

which- Figure 1 is a sectional view showing a wedge key of my improved construction in position between a shaft and a hub or collar positioned on said shaft. Fig. 2 is a section taken on the line 2-2 of Fig. 1. Fig. 3 is an elevation of a shaft provided with a key way-or recess adaptedto receive a wedge key of my improved construction; Fig. 4 is a sectional view similar to Fig. 1 and showing a modified form of the wedge key.

,Fig. 5 is a vertical section taken on the line 5-5 of-Fig. 4:.

My intention relates to that class of devices known as wedge keys and which are ordinarily employed in looking hubs, collars and sleeves to a shaft or spindle.

The object of my invention is to produce a simple, inexpensive wedge key, which is adapted to be seated in a specially formed key way or recess in a shaftor spindle, and" which wedge key and key way are formed so that the wedge key will automatically adjust itself in the key way or seat when forced thereinto, and into the groove or key way formed in the hub, sleeve or collar, that is locked by said wedge key.

A further object of my invention is to.

provide a' simple wedge key particularly adapted for use in a key way or seat which can be easily and quickly formed in a shaft or spindle without the use of a special form of cutting tool. 1 v

My invention consists in a wedge key which is approximately square in cross section, and which has two of its faces curved throughout their length, thus forming a, key

' body which tapers toward both ends, and

which key is utilized in connection with a key seat having a pair of opposite, longitudinally curved inclined faces.

To the above purposes my invention consists in certain novel features of construction hereinafter more fully described and claimed.

curved, oppositely inclined faces, and which key way has the greatest depth at its centerand gradually tapers toward its ends.

4 designates the hub or collar which is looked upon the shaft 1 by means of myim- 1 proved wedge key and formed within the opening in'said hub or collar is a longitudinally disposedV shaped groove 5 of slightly tapering depth throughout its length. The faces forming the bottomof this groove are arranged on angles of approximately 90 with respect to each other, and the greatest width of this groove 5 equals the greatest width of the key way or seat 2.

My improved wedge key 6 as shown, is in the form of an.elongated metal block subs'tantially square in cross section, and having a pair of straight plane longitudinally ex: tending upper faces 7 which when the key is properly seated bear against the corresponding faces ofthe groove 5. The lower faces 8 of the wedge key curve gradually throughouttheir length and said curved faces bear against the corresponding curved faces 3 forming thebottom of the key w'ay2 when the key is properlypositioned between 8 of the'key bearing directly against the corresponding curved faces 3 of the key seat permit the keyto automatically adjust itself when being positioned between the shaft and hub, and-when the hub is driven to a tight position on'the shaft, the greater portion of the key is inclosed by said hub, and it is, therefore, impossible for the key to become accidentally displaced from its seat.

In the modified construction shown in Figsfll and 5, the key seat is provided at its the shaft and hub. The curved lower faces center with a pair of vertically disposed parallel faces t), the lower edges of which join the inclined faces 3, and where such form of key seat is provided the key is provided on its sides with COIICSPOIlClllIg flat parallel side faces 10 betweenthe faces 7 and 8. In this modified construction a special form of cutter or tool necessary to form the key seat, whereas, in the preferred construction the key seat can be easily and quickly formed with .an'ordinary angular rotary cutter.

My improved wedge key is comparatively simple, can be utilized wherever 1t is necessary to look a hub, collar or sleeve to a shaft or spindle, is very effective in use, and by the formation of the curved faces in the bottom of the seat, and on the under side of the the seat when key, said key automatically adjusts itself in inserted between the shaft and hub.

It will be readily' understood that minor changes in'the construction and combination of the various parts of my device may be .made and substituted for those herein shown and described, without departing from the Spirit of my invention, the scope of which is set forth in the appended claims.

I claim k A 1. The combination with a shaft in which is fo rmed a key seat that is provided with a pair'of inclined faces arranged at an angle of approximately -90 degrees apart, which faces are gradually curved throu 'hout the length of the key seat so that sai key seat gradually decreases in depth and gradually tapers in Width toward its ends, of a hub adapted to be positioned on said shaft, which hub isprovided with a V-shaped groove, the faces of which occupy planes approximately 90? apart, and a wedge key adapted to be insertedin the coinciding groove and key seat, which key is provided on its underside with a pair of inclined faces that are curved lengthwise, and which are adapted to fit against the corresponding faces of the key seat in the shaft, and which key is provided on its upper side with a pair of oppositely inclined straight faces adapted to cooperate with the corresponding faces of the V-shaped groove in .the hub.

2. The combination with a shaft having a key seat that'is substantially V-shaped in cross section and the oppositely inclined faces of which are gradually curved throughout their length, and a hub or collar having a V-shaped groove, of a wedge key adapted to be inserted in-the coinciding key seat and V-shaped groove, which wedge key is provided. with a. pair of longitudinally disposed straight faces that cooperate with the corresponding faces of the \l -shaped groove in the hub, and said key being pro: vided with a pair of oppositely disposed,

longitudinally curved faces that cooperate WILLIAM G. KIRCHHOFF.

\Vitnesses:

F. R. CORNWALL, T. W. RnrNMERs. 

